breez-sdk-liquid/packages/react-native/DEVELOPING.md

Setting up a development environment

The Breez Liquid SDK React Native plugin consumes the underlying Breez Liquid SDK from the following sources:

• For iOS: The Breez Liquid SDK Swift bindings are integrated via CocoaPods.
• For Android: The Breez Liquid SDK Android bindings are integrated via Jitpack.

When developing, it can be useful to work with a locally built version of the Breez Liquid SDK instead of relying on what is published already on CocoaPods / Jitpack. To do this, you first need to build the Breez Liquid SDK bindings locally and then point the plugin to make use of the locally built Breez Liquid SDK bindings.

All the following commands can be run in the packages/react-native directory.

Prerequisites

Set the ANDROID_NDK_HOME env variable to your SDK home directory:

export ANDROID_NDK_HOME=<your android ndk directory>

To lint the result of the code generation ktlint, swiftformat and tslint need to be installed:

brew install kotlin ktlint swiftformat
yarn global add tslint typescript

On first usage you will need to run:

make init

Building the bindings

Then to build and copy the Kotlin, Swift and React Native bindings into the React Native package run:

make all

This will generate the following artifacts:

• iOS
  • ios/BreezLiquidSDKMapper.swift
  • ios/BreezLiquidSDK.m
  • ios/BreezLiquidSDK.swift
  • ios/bindings-swift/breez_liquid_sdkFFI.xcframework
  • ios/bindings-swift/Sources/BreezLiquidSDK/BreezLiquidSDK.swift
• Android
  • android/src/main/java/com/breezliquidsdk/breez_liquid_sdk.kt
  • android/src/main/java/com/breezliquidsdk/BreezLiquidSDKMapper.kt
  • android/src/main/java/com/breezliquidsdk/BreezLiquidSDKModule.kt
  • android/src/main/jniLibs/arm64-v8a/libbreez_liquid_sdk_bindings.so
  • android/src/main/jniLibs/armeabi-v7a/libbreez_liquid_sdk_bindings.so
  • android/src/main/jniLibs/x86/libbreez_liquid_sdk_bindings.so
  • android/src/main/jniLibs/x86_64/libbreez_liquid_sdk_bindings.so
• Typescript
  • src/index.ts

Building for one platform only

You can also build for Android or iOS only, in that case run:

make android react-native

or

make ios react-native

Using the locally built bindings

To use the locally built bindings instead of integrating them remotely, make the following changes:

• For iOS:
  • Rename the podspec files in packages/react-native/:
    • Rename breez_liquid_sdk.podspec to breez_liquid_sdk.podspec.prod
    • Rename BreezLiquidSDK.podspec.dev to BreezLiquidSDK.podspec
• For Android:
  • Comment out the following line from the dependencies section in packages/react-native/android/build.gradle:
    • implementation("com.github.breez:breez-liquid-sdk:${getVersionFromNpmPackage()}") { exclude group:"net.java.dev.jna" }

Reinstall the dependencies in the example project and run it. It will now use the locally built bindings.

Testing with the example app

To test locally built bindings in the example app, the npm dependencies need to be updated to use the local package. In packages/react-native/example/package.json replace the current version with file:../:

    "@breeztech/react-native-breez-liquid-sdk": "file:../",

Run the npm/yarn install to download dependences for both the react-native-breez-liquid-sdk package and the example app:

yarn bootstrap

Finally in the packages/react-native/example/ directory start either the iOS or Android app:

yarn android

or for iOS:

yarn ios

Troubleshooting

In case you get an error like:

java.lang.RuntimeException: Unable to load script. Make sure you're either running Metro (run 'npx react-native start') or that your bundle 'index.android.bundle' is packaged correctly for release.

Then manually run npx react-native start in the example directory and reload the app.